고지방식이 유도 비만 마우스에서 아연 보충이 골격 근육의 아연 수송체 ZIP7 수준과 혈당 조절에 미치는 영향

• Published in: Journal of nutrition and health Vol. 54; no. 6; pp. 594 - 602
• Main Authors: 주치앤징(Qianjing Zhu), 정자용(Jayong Chung)
• Format: Journal Article
• Language: Korean
• Published: 한국영양학회 2021
• Subjects: 생활과학; zinc transporter; skeletal muscle; mice; obesity
• ISSN: 2288-3886; 2288-3959
• DOI: 10.4163/jnh.2021.54.6.594

Purpose: The zinc transporter ZIP7 is known to regulate glucose metabolism in skeletal muscles, and skeletal muscles are known to play a critical role in glycemic control. The present study examines the effects of dietary zinc supplementation on the blood glucose concentration and expression of ZIP7 in skeletal muscle obtained from obese mice fed a high-fat diet (HF). Methods: C57BL/6J male mice were divided into three groups and were administered either a HF (60% of total calories from fat), HF supplemented with zinc (HF+Zn, 60% calories from fat + 300 mg zinc/kg diet), or low-fat diet (CON, 10% calories from fat), for 15 weeks. Results: Compared to CON group mice, the final body weights and adipose tissue weights were significantly increased, while the skeletal muscle weights were significantly decreased in mice belonging to the HF and HF+Zn groups. The HF+Zn group had significantly lower levels of fasting blood glucose concentrations than the HF group. Similarly, zinc supplementation significantly decreased the HF-elevated area under the curve values obtained from the oral glucose tolerance test. Skeletal muscle protein levels of ZIP7 in samples obtained from the HF group were significantly decreased as compared to the CON group. Conversely, the skeletal ZIP7 protein levels in the HF+Zn group were significantly increased as compared to the HF group. Moreover, the protein levels of phosphorylated-AKT and glucose transporter 4 in the skeletal muscle were significantly increased subsequent to zinc supplementation. Conclusion: Our data demonstrates that zinc supplementation up-regulates the skeletal muscle ZIP7 expression, which is associated with improved glucose tolerance in the obesity. 본 연구는 고지방식이로 유도한 비만 동물모델에서 아연의 식이를 통한 보충 급여가 혈당 조절과 골격 근육의 ZIP7의 작용에 미치는 영향에 대해 살펴보았다. 고지방식이를 공급한 HF군은 정상 대조군에 비하여 단위 체중당 골격 근육 무게가 유의하게 감소하였으며, 혈당은 유의적으로 증가하였다. 고지방식이와 함께 아연을 보충 공급한 HF+Zn군은 아연을 보충하지 않은 HF군과 비교하여, 공복 혈당과 경구 포도당 부하 후 혈당 증가 면적이 유의하게 감소하였다. 또한, HF+Zn군은 HF군에 비해 골격 근육의 ZIP7 단백질 수준이 유의하게 증가하였으며, AKT 활성과 GLUT4 단백질 수준도 유의하게 증가하는 것으로 나타났다. 이상의 결과를 종합해 볼 때, 아연 보충은 비만으로 인한 고혈당 증세를 완화하는 효과를 나타내며, 이는 골격 근육에서의 ZIP7 아연 수송체에 의한 당 대사 조절과 관련이 있을 것으로 생각된다.